The Taking Of Annie Thorne, C J Tudor

THEN One night, my little sister went missing. There were searches, appeals. Everyone thought the worst.

And then, miraculously, she came back. She couldn't, or wouldn't, say what had happened. But she wasn't the same afterwards.

She wasn't my Annie. Because sometimes my own little sister scared me to death . . .

NOW The email arrives in my inbox:I know what happened to your sister. It's happening again .